A Novel Approach to Assess the Dynamics of Extra-Chromosomal Circular Ribosomal DNA in Human Cells
Several nutrient-signaling pathways that extend life span have been described in model organisms.Ã‚Â Thus, parallel and redundant signaling pathways that are similar across species might be subject to experimentalÃ‚Â manipulation. Here, we develop a PCR-based technique for testing the hypothesis that mitoticÃ‚Â accumulation of extra-chromosomal ribosomal DNA circles might also determine life span inÃ‚Â human cells. Using resveratrol, a phytochemical that counters age-related signs, we find treatment-dependentÃ‚Â subcellular accumulations of extra-chromosomal 5S ribosomal DNA in human cell lines. TheseÃ‚Â data suggest an association between DNA circles and intrinsic aging and demonstrate the utility of a PCRbasedÃ‚Â technique for studying the accumulation of dysfunctional molecules that promote senescence.